%% Demo SVD 
disp(' -----------------------Image compression ------------------')

for im=1:1%3
    disp(['Read image no ' int2str(im) ' ... '])
  switch im
      case 1,
       Image=imread('bandit','jpg');
       kk=[5,20,50];
     case 2,
       Image=imread('Ekkore1024','jpg');
       kk=[10,20,50];
     otherwise
       Image=imread('Mart3','jpg');
       kk=[3,20,50];
end
disp('... Done.')
figure(1),clf,image(Image),axis('equal')
ImD=im2double(Image);
M1=ImD(:,:,1);
M2=ImD(:,:,2);
M3=ImD(:,:,3);

disp('Compute the SVD... '),tic
[U1,S1,V1]=svd(M1);
[U2,S2,V2]=svd(M2);
[U3,S3,V3]=svd(M3);
figure(2),clf
semilogy(diag(S1),'o'),hold,semilogy(diag(S2),'dr'),semilogy(diag(S3),'pg')
disp(['... Done within ' num2str(toc) ' sec.'])
wait
%% Compression 
kk=[3,20,50];
for s=1:length(kk),
    k=kk(s);
    N1=U1(:,1:k)*S1(1:k,1:k)*V1(:,1:k)';
    N2=U2(:,1:k)*S2(1:k,1:k)*V2(:,1:k)';
    N3=U3(:,1:k)*S3(1:k,1:k)*V3(:,1:k)';
    N1 = adjust(N1);
    N2 = adjust(N2);
    N3 = adjust(N3);

    clear ApIm
    ApIm(:,:,1) = N1;
    ApIm(:,:,2) = N2;
    ApIm(:,:,3) = N3;
    
    figure(s+2),clf,image(ApIm),axis('equal')
    title(['Number of vectors: ' int2str(k) ' out of ' int2str(size(Image,2))])
    xlabel(['The savings are :'  num2str(100-k*100/size(Image,2)) ' %'])
    wait
end
end

close all